Interaction of fission gases with liquid sodium and their detection by gamma spectrometry for the identification of failed fuel subassembly with gas leaker fuel pin in PFBR.

Identification of a failed fuel subassembly due to the dry rupture of its fuel pin in prototype fast breeder reactor is one of the safety protocols to be standardized for its safe operation for which interaction of fission gases with liquid sodium was studied. This paper reports the studies on the feasibility of detection of fission gases in presence of sodium as well as separation of fission gases out of liquid sodium through Ar purge in a prototypical sodium module with 300 mL of Na. The resultant gases were adsorbed on activated charcoal and determined the activity of fission gases using high resolution gamma spectrometry. Quantitative recovery of fission gases from sodium matrix in the range of sub-picogram levels was established. [ABSTRACT FROM AUTHOR]